From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC03DC4321E for ; Thu, 7 Apr 2022 01:31:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241104AbiDGBam (ORCPT ); Wed, 6 Apr 2022 21:30:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240517AbiDGBUD (ORCPT ); Wed, 6 Apr 2022 21:20:03 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FB5E3EBAF; Wed, 6 Apr 2022 18:17:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BC85B61DA4; Thu, 7 Apr 2022 01:17:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40069C385A1; Thu, 7 Apr 2022 01:17:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649294271; bh=/9/EoeSHUACmbJ7HvXHZB554Rh0bzWIVC1Sfe8QGiZQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Id9F8qHtctjTYhTw8PRQKs0NKolNDaMfeydFLAyBtH5UgD1L2Ir6Gec0RoJdrcceM cYu3HvbISXd6Y0cAvJQP/Ak8XfEeduCELwaD7eurEun1D2Ux5Me2TCvbkqelPxcajB dtEPgkhX+WakeRsjoizkscPwVQ/Sml5JLJRnKx1YfI02Upotjqp+wXdeputdADdoEc xOU5skwLdh5z9Uob6xNqOkuApP/Ke3e7rqcac7TuU7eWbTiZ2A7S0TuxwqHUegMV5g F7JlKdrx32cEBG11GHnz0XkFpbLqGw7uFN/0MOjKb8eg1DPaahUP1wqOQFHdO5xGXh uJibc62EZuRZg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Glenn Washburn , Richard Weinberger , Sasha Levin , anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net, linux-um@lists.infradead.org Subject: [PATCH AUTOSEL 4.9 3/7] um: port_user: Improve error handling when port-helper is not found Date: Wed, 6 Apr 2022 21:17:36 -0400 Message-Id: <20220407011740.115717-3-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220407011740.115717-1-sashal@kernel.org> References: <20220407011740.115717-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Glenn Washburn [ Upstream commit 3cb5a7f167c620a8b0e38b0446df2e024d2243dc ] Check if port-helper exists and is executable. If not, write an error message to the kernel log with information to help the user diagnose the issue and exit with an error. If UML_PORT_HELPER was not set, write a message suggesting that the user set it. This makes it easier to understand why telneting to the UML instance is failing and what can be done to fix it. Signed-off-by: Glenn Washburn Signed-off-by: Richard Weinberger Signed-off-by: Sasha Levin --- arch/um/drivers/port_user.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/um/drivers/port_user.c b/arch/um/drivers/port_user.c index 9a8e1b64c22e..d3cf5db1350a 100644 --- a/arch/um/drivers/port_user.c +++ b/arch/um/drivers/port_user.c @@ -5,6 +5,7 @@ #include #include +#include #include #include #include @@ -175,6 +176,17 @@ int port_connection(int fd, int *socket, int *pid_out) if (new < 0) return -errno; + err = os_access(argv[2], X_OK); + if (err < 0) { + printk(UM_KERN_ERR "port_connection : error accessing port-helper " + "executable at %s: %s\n", argv[2], strerror(-err)); + if (env == NULL) + printk(UM_KERN_ERR "Set UML_PORT_HELPER environment " + "variable to path to uml-utilities port-helper " + "binary\n"); + goto out_close; + } + err = os_pipe(socket, 0, 0); if (err < 0) goto out_close; -- 2.35.1